Machine tools



1957 J. F. KOPCZYNSKI 2,801,859

MACHINE TOOLS Filed Jan. 12, 1956 3 Sheets-Sheet 1 IN VEN TOR.

J0 op agynsih' C? gar/re y s.

Aug. 6, .1957 J. F. KOPCZYNSKI 2,

MACHINE TOOLS Filed Jan. 12, 1956 I 5 Sheefs-Sliet 21 CH FmWe S.

INVENTOR. 4

BY w,

1957 J. F. KOPCZYNSKI 2,801,859

MACHINE TOOLS Filed Jan. 12, 1956 3 Sheets-Sheet 3 INVENTOR.

rate atent This invention relates to machine tools, andtparticularly tothe detachable mounting of punches.

An object of the invention is to provide .an improved mounting "for perforating punches, which will always hold a punch accurately in a selected, angular position relatively to its longitudinalaxis, which will effectively -resist the pulling forces onthe punch when the latter is stripped from the material it has perforated, which will provide fora maximum areaofhold on the punch for maximum distribution ofthe stripping forces, which will resist any tendency of the punch to fracture at its shank while the punch is being stripped from the work, which will provide simplicity of mounting, and ease and accuracy of removal of the punch and repositioning after sharpening.

Another object is'to provide a retainer for a punch 'with which onecan remove and replace a punch while 'theretainer is still in the punch press, which will lock the punch-securely against pulling out during its use, 'and which'will accuratelylocate or position'the punch radially or angularly of the socket or recess in which the punch is held,so that a punch of non-circular shape willbe always properly and accurately alined with its mating die or the die button.

Afurther "object is to provide an improved, simple, durable, practical and relatively inexpensive mounting of removablepunches, which will effectively hold the punch snuglyinthe desired position, and with'which the punch may be quickly and easilyrernoved or replaced in the mounting.

Other objects and advantages will be apparent from the following description of several embodiments of the invention and the novel features willbe particularly pointed out hereinafter in connection with the appended claims.

In the accompanying drawings:

Fig. 1 is a side elevation of my improved punch and its retainer illustrating one example of the invention;

Fig. 2 is a sectional plan of the same, the section being taken approximately along the line 2-2 of Fig. l;

Fig. 3 is a vertical, sectional elevation of the same, the section being taken approximately along the line 33 of Fig. 2;

Fig. 4 is another sectional plan of the same, the section being taken approximately along the line 4-4 of Fig. 3;

Fig. 5 is an enlarged, vertical, sectional elevation of the same, the section being taken approximately along the line 5-5 of Fig. 3;

Fig. 6 is an enlarged elevation of an end of the punch.

Fig. 7 is an enlarged elevation of the locking pin or member.

Fig. 8 is a vertical, sectional elevation of a punch and its retainer or holder, and illustratinganother example of the invention;

Fig. 9 is a sectional plan of the same, the section being taken approximately along the line 99 of Fig. 8;

Fig. 10 is an enlarged, sectional elevation of the same, the section being taken approximately along the line 1010 of Fig. 8;

Fig. 11 is a view similarto Fig. 10 but with the punch released;

Fig. 12 is an elevation of the locking pin or member of the same;

with screw threads.

Fig. 13 is anend elevation of the. locking member; .Fig. 1 3a.is .a cross sectional elevation of the. same the section being-taken approximately along the line 13a13a of Fig. 12;

Fig. 14 is a sideelevation. of a punch and its retainer constructed in accordance with this invention, but illustrating another exampleof it;

Big. 15 is asectional plan -of-the same, the section being -taken approximately :along the line 15-15 of Fig. 14;

Fig. 16 is an enlarged, sectional elevation ofthe same, the section being taken approximately along the line 16-16 ofFig. ,14;

Fig. 17 is a view similar to Fig. 16, but showing the punch in the process of removal or replacement; and

Fig. 18 is a planet the locking pin or member used in this example of the invention.

(In the example of the invention illustrated in-Figs. l to 7, a retainer block. 1.is detachably located and confined to a ram or hardened die plate 2, by means of "dowel pins 3 and screws 4. The block 1 is provided in its lower-face Witha recess 5 that extends vertically through the blockfromend face to end face, in which the head or shank of a-perforatingtpunch 6 may be ,received andheld. The block 1 also has a passage 7 therein'from end'face to endface, which is oblique to "the longitu'dinl axis of therecess, and intersects with one side of -'the recess '5. This passage 7 is tapered upwardly and at its smaller, upper end, it terminates in a short cylindrical part8 of the passage that is provided 'A-locking pin or member'9, also similarly tapered, is disposed in the passage, andtthe smaller end of the member9 terminates in a short cylindrical partlllfthatis threaded to engage with the threads of part s ofthe passage.

Since'the passage "7 intersects with one side of the recess"5, the pin or, member 9 will crossone side ofthe parallel to the axis of' the passage "7 and extends along recess 5. 'fThehead of the punch 6 which is received in the recess "5is provided with an oblique, arcuate, taperedgroove 16 which may be'milled therein and is the intersection, so that when the punch 6 is rotated or disposedin the. recessto bringithe groove 10 along the intersection, the locking pin or member 9 can be inserted into the passage'7 and threaded into the small,

threaded end 8 of that passage The niember 9 will pass along and fill the groove 10, whichis part of a cylindrical surface, and engagein the groove 10 of the lockingmember so. as to securely and firmly confinethe punch 6 within the recess 6. The locking pin thus Wedges'or cams the punch upwardly and sidewise. The dimension of the punch from its top down to the groove or notch 10 shouldpreferably be a few thou'sandths of an inch longer than the same corresponding distance along the recess, so that the tapered locking pin will push or wedge'thepunch upwardly or impart to it'an upward pre-load. The lower and larger end of the locking pinor member 9 is formed to receive a turning tool, such as by providing in the said face of the mem- "ber 9, a. non-circular cavity 11 (Fig. 7), and a square or hexagon socket, in which a wrench may be inserted to turn the member whenever it is inserted to lock the punch or removed to release the punch.

In the example of the invention illustrated in Figs. 8

v to 13 and 13a,the block 12 is secured against a hardened member 21 which has a head 22 at one end that is received in the passage end of larger diameter. The head 22 limits descent of the locking pin or member down the passage, and the head 22 of member 21 engages against the hardened plate 13, the free end face of the head having its corner edge bevelled off at 23 for most of the periphery of the head, so that the bevelled part will abut flatly against a face of plate 13, as shown in Fig. 8. This confines the locking pin or member 21 against endwise movement along the passage 19, but it is free for limited rotation in the passage. The passage 19 extends obliquely of the length of the recess 17 from one end face of the block to the other, and it intersects somewhat with one side of the recess 17 in the same manner that the passage 7 intersected the recess 5 in Figs. 1 to 7. Hence, the locking pin or member 21 will extend obliquely across one side of the recess 17. The head of the punch 18 is provided on one side of the part which is within the recess 17 with an oblique, arcuate channel or groove 24 which is a part of a cylinder that lies along and is parallel with the passage 19 when the head of the punch is fully within the recess 17, so that the locking member 21 may fill this groove 24 and lock the punch firmly in the recess, and also wedge the punch upwardly against the plate 13.

In order to be able to easily and quickly release the punch without removing the block 12 from ram 14, the locking member is provided in its side along the intersection between the passage 19 and the recess 17 with an oblique, arcuate groove 25 which is partially cylindrical in shape, so that when the member 21 is rotated in the passage 19 to bring its groove 25 along the intersection, as shown in Fig. 11, the groove 25, which then lies along the recess, will conform to the cutoff portion of the recess at the intersection, and hence member 21 will not then enter the recess 17. This releases the punch head so that the punch 18 can be withdrawn, as shown in Fig. 11, and sharpened and then replaced, or replaced with a diiferent punch. To enable rotation of the locking member or pin 21, the lower end face of that member is formed to receive a turning tool, such as to have a non-circular cavity 26 (Fig. 12) into which the correspondingly shaped end of a wrench may be inserted through the lower end of the passage.

When the punch head is reinserted into the recess 17, the punch will pass along and fill the groove 25 of the locking member until the punch head is fully within the recess and abuts plate 13. This alines the groove 24 of the punch head with the intersecting part of the passage 19, after which rotation of the locking member will carry its oblique groove 25 away from the recess 24 and the cylindrical part of the member 21 will enter and fill the cylindrical, oblique groove 25 and lock the punch firmly in the recess, as shown in Fig. 10. By this operation the engagement of the member 21 with the oblique groove 24 will wedge or cam the punch upwardly and tightly against the plate 13, as explained for Figs. 1 to 7. The unbevelled part 27 of the head 22, by engagement with the plate 13, will limit rotation of the locking member and serve to indicate the rotary position of the groove 25. The dot and dash line 28 in Fig. 13a indicates how the radius of the lead end of member 21 is reduced to provide for a wedging or camming action of the member 21 in the groove in the punch when the-member 21 is turned in a counterclockwise direction in Fig. 13a.

In the example of the invention illustrated in Figs. 14 to 18, the block 30 is removably confined to the ram or die member 31, with an interposed, hardened plate 32, in any suitable manner, such as by dowel pins 33 and screws 34. The dowel pins are provided in the block and are received in openings in the plate 32 and member 31. The block 30 is provided with a recess 35 extending from face to face thereof, in which recess the head of a punch 36 may be removably received; The block 36 is provided with a passage 37 also from end face to end face of the block, but in a direction oblique to and olfset 4 from the longitudinal axis of the recess 35 and intersecting with one side of the recess, as shown in Figs. 15, 16 and 17. This passage 37 is tapered downwardly and at its lower end it becomes cylindrical and is there threaded.

A locking pin or member 38, which is tapered the same as, and which fits the passage 37, terminates at its smaller end in a cylindrical part 39 which is threaded and screwed into the threaded, cylindrical end of the passage 37. The small, threaded end 39 is provided with a non-circular socket 40 which receives the non-circular end of a wrench, inserted through the lower end of the passage 37, by which the member 38 may be rotated. The head of the punch 36 is provided with an arcuate groove 41 in its side along the intersection of recess 35 with the passage 37, the groove 41 extending along and conforming to the cutaway wall of the passage at the intersection, so that the member 38 will fill the groove 41 and lock the punch in the recess 35, as shown in Fig. 16. The member 38 is provided with an oblique, arcuate groove or channel 42 that lies along the intersection between passage 37 and recess 35 when the member 38 is rotated in the passage so as to bring the groove 42 to the intersection.

The size and shape of the groove 42 conforms to the cutaway wall of the recess 35 at the intersection, so that when the groove 42 is alined with the intersection with recess 35, the wall of this groove will form a continuation of the recess wall or at least clear it. This makes it possible to insert or remove a punch as shown in Fig. 17. When the punch is fully within the recess 35 and its oblique groove 41 is alined with the intersection, one may rotate the locking member 38 and move its uncut periphery into the oblique groove 41 in the punch head, which will lock the punch firmly in the recess and cam it snugly and endwise against the plate 32, as shown in Fig. 16.

It will be observed that in all examples of the invention, the locking member positions or locates the punch angularly in the recess in which the punch is confined so that if the punch has a non-circular perforating end, it will always be disposed in the same proper alinement with its mating die member. The locking member, because of its oblique position, serves to cam or wedge the punch endwise of itself firmly against the plate or element against which it abuts. In the stripping operation, following a perforation of sheet material by the punch, where the punch is pulled out of the sheet material, there is a heavy stress on the punch at the part where it is held, whether it be a shoulder, a bridge lock, as in prior devices, or on the ball seat in other punches. This stress, at times, becomes so great that the heads pop off or the bridge-locked punches crack at the holding recess, or the ball seat type punches jam at their taper back points. With the present invention, the locking action is diagonal to the shank or head of the punch, thereby distributing the stripper load throughout a large portion of the shank or head of the punch, thereby eliminating a fixed, concentrated weak point. This groove that is machined into the punch itself is an arcuate one composed of a radius, thereby eliminating any sharp corners in the interior of the punch. This is an important feature in the heat treated steels, where it is desired to eliminate potential fracture points. 7

It will be understood that various changes in the details and arrangements of parts which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.

I claim:

1. A holder for a perforating punch comprising a die plate, a block removably confined to said plate and having a recess therein to receive and hold the head of a punch, and also having a passage from face to face therethrough and obliquely intersecting a side of said recess,

a locking member confined in said passage but rotatable therein about the longitudinal axis of said passage, said member having an arcuate groove in its side at the intersection of said passage and said recess which clears said recess when in one rotative angular position, but enters said recess when rotated in said passage through a partial revolution, whereby when the head of a punch is received in said recess and has an oblique groove in a side thereof at the intersection of the recess and passage, rotation of said locking member will cause the member to enter the recess and the groove in the punch head and lock the punch head firmly, but removably in said recess.

2. A holder for a punch comprising a block having a recess therein to receive and hold the head of a punch and also having a passage obliquely intersecting one side of said recess and having its opposite ends extending beyond said recess, a locking member removably confined in said passage and extending across said intersection with said recess, whereby when the head of a punch is disposed in said recess with an. oblique groove at said intersection, said member will enter said groove, lock said punch head in said recess, and hold it against rotation in said recess.

3. A punch unit comprising a block having a recess therein opening through a face of the block, and also having a passage obliquely intersecting one side of said recess, a punch having a head received in and fitting said recess with a groove oblique to the length of the head in one side thereof at said intersection and approximately alined with said passage at the intersection, and a locking member extending along, fitting and removably confined in said passage and entering and extending along said oblique groove to removably confine said punch head firmly in said recess and hold it against rotation in said recess, an end face of said locking member having a non-circular cavity therein to receive a tool by which said member may be operated to release said punch head.

4. A punch unit comprising a plate, a block secured to said plate and having a recess therein opening from an end face thereof, said block also having a passage therein obliquely intersecting said recess and having its opposite ends extending beyond said recess, a locking member removably confined in said passage for rotation about the longitudinal axis of the passage and extending somewhat into and across said recess at said intersection, but having a cutofi segment at the recess intersection which, when the locking member is rotated to hung the cutoff portion at the side of the passage along the intersection, will clear said recess, a punch having a head received in said recess with a groove in a side thereof, at the intersection, extending in a direction obliquely of the length of the head and approximately parallel to and alined with said passage, whereby rotation of said locking member to bring an uncut portion into said groove will lock said punch head firmly in said recess, and rotation of it to bring its cutoff portion to the intersection will release said punch head.

5. A punch unit comprising a plate, a block secured to said plate and having a recess therein opening from an end face thereof, said block also having a passage therein obliquely intersecting said recess, a locking member removably confined in said passage for rotation about the longitudinal axis of the passage and extending somewhat into and across said recess at said intersection, but having a cutofi segment at the recess intersection which, when the locking member is rotated to bring the cutoff portion at the side of the passage along the intersection, will clear said recess, a punch having a head received in said recess with a groove in a side thereof, at the inter section, extending in a direction obliquely of the length of the head and approximately parallel to and alined with said passage, whereby rotation of said locking member to bring an uncut portion into said groove will lock said punch head firmly in said recess, and rotation of it to bring its cutoff portion to the intersection will release said punch head, said locking member and passage being tapered at the intersection, and said. member having its smaller end threaded into said passage to secure it therein for rotation.

6. A punch unit comprising a plate, a block secured to said plate and having a recess therein opening from an end face thereof, said block also having a passage therein obliquely intersecting said recess and having its opposite ends extending beyond said recess, a locking member removably confined in said passage, and having a side portion extending somewhat into a side of said recess at said intersection, a punch having a head received in said recess and a groove in a side of said head, at the intersection that extends along and in the same oblique direction as said passage when the head is positioned in the recess with said groove at the intersection, whereby said member locks said punch firmly in said block recess and positions it angularly in said recess.

'7. A holder for a punch comprising a plate, a block removably confined to a face of said plate and having a recess in its face opposite from said plate, and also a passage therethrough from said opposite face to its face which abuts said plate, said passage extending obliquely of the longitudinal axis of said recess and intersecting with a side of said recess, a locking member removably confined in said passage with a side thereof extending somewhat into and obliquely across said recess, whereby when the head of a punch is received in said recess, with an oblique groove in its side at the intersection that is approximately parallel to and along said passage, the projection of a side of said member into said groove will lock said punch in said recess and position it angularly in said recess, said passage being tapered endwise as it passes said intersection and threaded at its smaller end, said locking member having a similar shape and size and threaded into said passage at one end thereof, the lower end of said member being formed for the application thereto of a turning tool.

8. A holder for a punch comprising a plate, a block removably confined to a face of said plate and having a recess in its face opposite from said plate, and also a passage therethrough from said opposite face to its face which abuts said plate, said passage extending obliquely of the longitudinal axis of said recess and intersecting with a side of said recess, a locking member removably confined in said passage with a side thereof extending somewhat into and obliquely across said recess, whereby when the head of a punch is received in said recess, with an oblique groove in its side at the intersection that is approximately parallel to and along said passage, the projection of a side of said member into said groove will lock said punch in said recess and position it angularly in said recess, said passage being cylindrical at the intersection, and said member having its part along the intersection also cylindrical and having a head at its upper end, said passage having an enlargement at its upper end to accommodate said head of said member, said cylindri cal part of said member at said intersection having the part of one side thereof which projects into said recess cut oif so as to clear the recess when a punch head is inserted or removed, whereby rotation of said member in said passage will bring an uncut side of said member into said recess to lock in the recess any punch head therein, the lower end of said member being formed for application thereto of a turning tool.

References Cited in the file of this patent UNITED STATES PATENTS 1,408,993 Eberhardt Mar. 7, 1922 1,785,495 Richard Dec. 16, 1930 2,128,116 Boone Aug. 23, 1938 

